Therefore, I estimate clustering-robust standard errors at the prefectural level, which allows correlations of disturbance among individuals who live in the same prefecture (Anglist and Pischke [22]).
However, the present study showed a remarkable difference among regions even within the same prefecture.
The change of inventory is estimated assuming that the inventory change's ratio to the output in an area is the same in the prefecture.
Thus, although the prefectural and municipality government workers were working as public servants in the same disaster-affected prefecture and the former were investigated at a time closer to the disaster, severe psychological distress was more common in municipality workers.
Newman's community analysis [17, 18] also shows that firms tend to transact with each other when they belong to the same industry and/or are located in the same state or prefecture [19].
Isolation of most of the clustered strains from hospitals in the same or neighboring prefectures may indicate that transmission is occurring in the communities.
Of the 9 clusters, 7 consisted of patients whose hospitals were located in the same or neighboring prefectures, and the remaining 2 clusters consisted of patients whose hospitals were located in the same region (i.e., a geographic and administrative area with several prefectures).
From June 2012 to July 2012, 33 PCPs, each of whom remained in the same facility in Mie prefecture (whether clinic, small-scale hospital, or large-scale hospital) for the preceding year were recruited for a preliminary web-form survey to ensure the feasibility and reliability of the questionnaire.
